In the formation of color paper it is known that the base paper has applied thereto a layer of polymer, typically polyethylene. This layer serves to provide waterproofing to the paper, as well as providing a smooth surface on which the photosensitive layers are formed. While the polyethylene does provide a waterproof layer to the paper, the melt extruded polyethylene layer on the backside of color photographic paper is coated with a functional layer that provides antistatic, writable, printable and frictional properties that aid the paper to be photofinished in a variety of equipment. Furthermore in the photofinishing of photographic paper, rolls of paper are exposed with customer negatives. When a roll of photographic is completely exposed, a second roll of non exposed paper may be spliced onto the end of the roll that was exposed. Spliced rolls provide efficiency to the photofinishing operation. Splices and are a way to join the ends of two or more rolls of photographic paper to make a larger roll of paper. Heat splices are commonly used in high speed printers. A heat splice is a device that supplies heat and pressure to two overlapping pieces of photographic paper. Two important criteria of heat splices are the strength of the bond and whether the paper sticks to the heat splice head. If the bond is too weak it can fail as the paper is transported through the printer, through the processor or through the cutter-sorter machines. If the paper sticks in the splice head, the printer cabinet must be opened to manually free up the paper and the paper in the machine is fogged. Photographic paper is conveyed through these machines at a high rate of speed. After the exposure step the rolls are then processed through photochemical processing solutions, dried and wound into rolls. The rolls are run through high speed cutters/choppers and finished into final customer prints. Throughout the photofinishing processing of exposure, processing, cutting and packaging it is important that the roll to roll splices have sufficient strength to hold the webs together without failure. If a splice breaks, there is considerable waste and expense incurred with reprints. This adds to the photofinisher cost and may delay a customer order or even worse it may result in the customer loosing invaluable pictures that are not readily be replaced.
It has been proposed in U.S. Pat. No. 5,244,861 to utilize biaxially oriented polypropylene in receiver sheets for thermal dye transfer. This invention provides a near photographic paper used in dye sublimation printers. The paper used in this process is in sheet form and therefore does not need to be spliced as is required for photographic applications. Japan Patent 7128764 reports the use of a water soluble polyester or copolymer comprising polyester and polyvinyl type polymers for improved adhesion for photographic X-rays materials and there is no indication of a fusible layer. Japan Patent application 7128763 refers to water soluble electroconductive materials.
In U.S. Pat. No. 5,391,472 an oriented polyester web is coated with a primer layer comprising a polythiohene, a latex polymer and a polymeric polyanion compound to provide good adhesion to the web substrate that withstands stretching.
U.S. Pat. No. 4,863,801 reports a crosslinked polymeric blend of at least two polymers comprising a reactive epoxy group and free H groups coated on a primed layer of ambifunctional silane coupling agent on a polyester substrate. Said layers provide good adhesion as well as some antistatic properties but does not adhere a separate antistatic layer to a substrate. In U.S. Pat. No. 3,234,025 reports a photographic element comprising a support and a layer of gelatin comprising a water soluble polyethyleneimine and urea is used to help prevent dye diffusion in the photographic image bearing colloid layers. U.S. Pat. No. 3,630,742 provides improved adhesion of emulsion to a polyester or polystyrene support with corona, polyethylene coating and a gelatin layer while U.S. Pat. No. 3,676,189 concerns itself with a polyolefin surface treated with a coating of an aqueous silica solution and a water insoluble film forming material for improved adhesion to photographic emulsions or printing inks. U.S. Pat. No. 4,042,398 provides improved adhesion of paper to a polyolefin film by applying an aqueous coating aluminum oxide.
In U.S. application Ser. No. 09/023,950, it has been proposed to use biaxially oriented sheet of polypropylene on both the top and bottom sides of photographic paper. This paper is coated with backside functional layers to enhance the antistatic and frictional performance of the paper. The backside polymer layer is predominately polypropylene with a terpolymer to provide a matte appearing surface. Since these polymers are dissimilar, there are discrete dominates of polymer that have slightly different chemical and physical properties. These differences can make it difficult to adhere materials such as an antistat to the surface. When compared to polyethylene, it is more difficult to adhere materials to a polypropylene surface. There remains a need for an improved means to adhere other chemicals to the surface of polypropylene.